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Q: After having battery disconnected, hazzard and dash lights are blinking, and key wont turn engine over.

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Service engine light was on, and starter wouldn't engage every time, so I checked for loose connection, the positive battery cable was loose. so I disconnected and then reconnected battery, and tightened the positive connection. That is when my problem started. the hazard and dash lights started blinking, and the key wont turn the starter at all. a mechanic friend says its the antitheft system, and I need to reset it. I tried locking and unlocking driver door lock with the key, which is sticky. Didn't work. then I left key in ignition at the on position for about 15 minutes. That didnt work either. Any suggestions?

My car has 134300 miles.
My car has an automatic transmission.

Hi there. The security alarm system was tripped and caused the computer to lock out the ignition system. Remove the battery cables (both) for 13 minutes. While the cables are off, operate all the components in the vehicle with the key in the on position. Even though there is no power, this will drain all of the power to the vehicle completely. Then turn off the key and remove the key. Hook up the battery cables and put the key in the driver door and lock and unlock the door 3 times. Then open the door and see if the engine will start up. If it does, then you have successfully reset the alarm. If the alarm is still being tripped, then there is a problem with the security control module, faulty key fob, or a faulty ignition switch and they may need to be replaced. If you need further assistance with diagnosing your security system, then seek out a professional, such as one from Your Mechanic, to help you.

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